All spell casters gain their abilities through a form of demon possession. So in order to gain magical abilites, PCs must track down and trap demons. Of course there are some pretty powerful demons, if the demon is stronger than the PC, the PC could find themselves subjugated to the Demon's will.
In cultures and langauges with very few acceptable personal and family names, nicknames will be used. These nicknames will be based on their physical traits and personalities. So instead of five Ryon Khans, you have Big Ryon, Little Ryon, Fast Ryon, Ryon the Priest, and Ryon with coin. It will make finding people, for an outsider, difficult.